feat(editor): adjust attachment block UI (#11763)

Closes: [BS-3143](https://linear.app/affine-design/issue/BS-3143/更新-attachment-错误样式)
Closes: [BS-3341](https://linear.app/affine-design/issue/BS-3341/attachment-select状态ui调整)

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit

- **New Features**
  - Improved attachment block with unified reactive state handling for loading, errors, and downloads.
  - Enhanced card layouts with modular rendering and dynamic buttons based on state.

- **Bug Fixes**
  - Fixed UI state for "Embed view" action, now correctly disabled when not embedded.
  - Resolved attachment card styling issues and text overflow with new utility classes.

- **Refactor**
  - Streamlined attachment block rendering and state management for better performance and maintainability.
  - Updated toolbar configuration for consistent parameter naming.
  - Simplified embedded and open methods for improved clarity.
  - Made internal functions private to reduce exported API surface.

- **Chores**
  - Removed unused icon export and legacy upload tracking functions.
  - Updated attachment utilities to use reactive state, added data refresh, and improved error handling.
  - Refined image dimension handling for consistent resizing behavior.
  - Improved test selectors to target focused attachment containers for better reliability.
  - Refactored CSS to separate container and card styling and adopt theme-based colors consistently.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/affine/components/src/icons/text.ts

@@ -340,11 +340,6 @@ export const FontFamilyIcon = icons.FontIcon({
   height: '20',
 });
 
-export const AttachmentIcon16 = icons.AttachmentIcon({
-  width: '16',
-  height: '16',
-});
-
 export const TextBackgroundDuotoneIcon = html` <svg
   xmlns="http://www.w3.org/2000/svg"
   width="20"